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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Diagnostika železobetonové konstrukce / Diagnostics of reinforced concrete structures

Holbová, Monika January 2017 (has links)
This diploma thesis deals with the building survey and diagnosis of the station building of a railway station in Vítkovice. It describes process of survey and evaluation of existing reinforced concrete structures and used diagnostic methods. The survey of the object is described in the practical part of the thesis, which involves location of testing spots, taking the samples for testing from the structure, laboratory testing and evaluation of the results – determination of compressive strength of concrete with classification of concrete and elastic modulus. The last part includes static calculation of selected part of the structure.
102

Vliv použitého kameniva na vlastnosti vápenných malt / The effect of aggregate type on the properties of lime mortar

Žižlavský, Tomáš January 2017 (has links)
The thesis is focused on the comparison of the role of different types of aggregates and the binder-aggregate ratio on the properties of lime mortars. The theoretical part of the thesis deals with the effect of properties of aggregate, a binder-aggregate ratio and a use of calcareous aggregate, especially limestone, on the properties of mortars. It also deals with the utilization of limestone as aggregate in a history of masonry. In the practical part of the thesis there is a comparison of physically-mechanical and microstructural properties of mortars prepared with different type of aggregate (siliceous sand and limestone aggregate), with varying binder-aggregate ratio and also with a partial substitution of the aggregate by limestone fines. It was found that the usage of limestone instead of quartz sand produces the mortar of comparable properties. The partial substitution of the aggregate with limestone fines caused noticeable growth of strength, especially in mortars with higher binder-aggregate ratio.
103

Průzkum a hodnocení zděné budovy zámečku / Survey and assessment of masonry building castle

Kopecký, Martin January 2017 (has links)
This diploma thesis deals with the diagnostics of masonry structures. In the theoretical part of this thesis it is described the system of assessment of existing structures and then the assessment of existing masonry structures. The next chapter states the methods of survey of masonry structures, including evaluation. The practical part of the thesis deals with the survey of the building of a small castle. This survey includes a brief history of the castle building, the preliminary inspection of the building and the research of the supporting structure. The result of the survey is to determine the material characteristics of masonry.
104

Studium a stanovení lipidů čmeláků chromatografickými metodami / Analysis of bumblebee lipids using chromatographic methods

Kudzejová, Michaela January 2010 (has links)
Lipids from the fat body of queens of Bombus terrestris species in different life stages were studied using chromatographic methods. High-performance liquid chromatography - mass spectrometry with electrospray ionization was used to analyze all lipids from the tissue. Semi- preparative thin-layer chromatography was used to isolate triacylglycerols (TGs) from the fat body tissue. The TGs were subsequently analyzed by high-performance liquid chromatography - atmospheric pressure chemical ionization mass spectrometry. Quantitative differences between different life stages have been found. Qualitative composition has not been changing significantly. Only minor differences have been found in the substances, which were present in amount less than 1%.
105

Využití alternativních pojiv do stmelených směsí z recyklátů / Use of alternative binders in bound mixtures from waste building materials

Jakub, Tomáš January 2022 (has links)
This diploma thesis is focused to use bonded base layers with different types of admixures for base layers of roads. The first, theoretical part of the work deals with summary of the available literature. Deals with basic and uncoventional type of admixures used for bonded base layers. The second, partical part of the work deals with comparsion of 5 bonded base layers with recycled asphalt with added artifical fibers, cellulose fibers or without admixures and one mixtures created only from First of all is described tesťs methods with design of mixtures and described materials. In the practical part of the work was tested compressive strength, transverse tensile strength and compressive strength after effects of frost. In the end of the work is comparsion all mixtures between themselves and determination effects admixtures on compressive strength and transverse tensile strength.
106

Stavební průzkum a diagnostika zděné konstrukce / Survey and Diagnostics of Brick Structure

Brothánek, Jan January 2022 (has links)
The diploma thesis deals with a structural and technical survey of the surviving cellar of the German House in Brno. The first part of the thesis is devoted to the theoretical description of the constructions, methods performed and their evaluation concerning the investigated space. The aim of the survey is to determine the strength characteristics of the masonry and on their basis to propose appropriate rehabilitation and structural protection.
107

Vlastnosti dřeva různého stáří s ohledem na tepelné namáhání / Properties of wood of different ages considering heat exposition

Helanová, Ester January 2012 (has links)
This thesis discusses the experimental verification of sorption and mechanical properties of fir wood from the 17th to 21th century. The wood of different ages is thermally treated with temperature of 60°C, 120°C and 180°C for a 17 hours. The effect of thermal treatment of wood on the isothermal sorption characteristics and compressive strength in fiber direction is evaluated.
108

Využití mikro a nanotechnologií pro vývoj ultra vysoce pevnostních a vysokohodnotných betonů se speciálními vlastnostmi / The use of micro and nanotechnology to develop ultra high strength and high performance concrete with special features

Vlč, Viktor January 2012 (has links)
The use of nanotechnology has become wide spread in all branches of science. Nanotechnology help us to understand microstructure and due to the world has started to produce new materials. One of many examples carbon nanotubes (CNTs). In diploma thesis I tried to find the way of successful introduction into concrete mixture. I was studying influence of CNTs and other nano particles and I was comparing them with referential samples (without CNTs). Also I tested the improvement of mechanical characteristics of concrete. The morphology of nano particles was studied using Scanning Electron Microscopy (SEM). The results show that introduction of nanoparticles to results in increasing strength and higher density. That is why High Performace Concrete so resistant and durable.
109

Návrh regulace tlaku a průtoku v soustavě čerpadlo-nádrž / Pressure and Flow Rate Regulation Design for Pump-Tank System

Kovář, Jiří January 2014 (has links)
The proposed work is dealing with control design of pump-tank system as part of broader water-supply network with using of mechatronic approach. The main goal of this work is design of control for regulation of flow, pressure and water level in tank in water-supply network of Vsetin city. This water-supply network consists of various components, such as pumps, pipes, valves, tanks etc. For the purpose of the control design is necessary to create a model of pipe network. The solution of hydraulic analysis is obtained by using the gradient method, which was implemented into the software solution named ADAM. The results of hydraulic analysis are compared with measured values of flow and pressure and difference of these values has to be minimalized by proposed calibration and verification process. The calibration and verification process was implemented in software ADAM. The essence of design control is formulating control problem as optimization problem. Therefore the output of higher control layer is set of procedural rules, which determines for example speed of pumps in time etc. Results were verified by using for this purpose developed computational server (ADAM Server).
110

Geopolymery na bázi elektrárenských popílků a cihelného střepu / Geopolymers based on fly ashes and brick body

Řezník, Bohuslav January 2014 (has links)
In line with the current focus on utilizing side products of various production processes, this dissertation thesis analyzes the process of alkali activation of particular side products: fly ash and brick fragments. This activation produces geopolymeric materials widely used in civil engineering. The thesis aims to optimize the geopolymerization process so that the resulting geopolymer is both ecologically and economically viable. To that end, the thesis studies the course of geopolymeric reaction between the alkali activator and fly ash from: (i) the Chvaletice power plant, (ii) the Dětmarovice power plant, and (iii) biomass combustion, as well as (iv) fluid fly ash from the Hodonín power plant. All experiments of geopolymeric reaction have focused on the factors influencing the synthesis of geopolymers—that is: composition of the alkali activator, the ratio of alumino-silicate to the activator, and the impact of temperature on structure of the synthesized geopolymer. Further, the thesis analyzed the synthesized polymer’s microstructure, phase composition, resistance against corrosive conditions, and compressive strength, as well as mechanical-fracture properties of selected fly-ash geopolymers. The thesis finds that the most suitable for geopolymeric synthesis appears to be the fly ash from the Chvaletice power plant in which case the obtained geopolymers showed best properties in the studied areas. The fly ash from the Dětmarovice power plant, biomass fly ash, and fluid fly ash have failed to reach acceptable properties. Separately, the thesis studies the geopolymerization of brick body that could be suitable input for alkali activation. The geopolymers synthesized from brick fragments resulted in materials of supperior mechanical strength. A mixed use of fly ash and brick fragments failed to show a synergetic effect. Properties of the resulting geopolymers have been inferior to the properties of geopolymers produced using just fly ash or just brick body.

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